US2102112A - Powder loading device - Google Patents

Description

Dec. 14, 1937.

J. c. COSTELLO 2,102,112 POWDEVR LOADING DEV-ICE Filed Sept, 3 1955 "a INVENTOR, JOSEPH c. COSTELLO.

ATTORNEYS Patented Dec. 14, 1931 UNITED STATES PATENT OFFICE 2,102,112 POWDER LOADING DEVICE Joseph C. Costello, San Francisco, Calif. Application September 3, 1935, Serial No. 38,993

2 Claims.

My invention relates to apparatus for loading bore holes with explosives, and more particularly to an improved machine for loading, seating and backiilling charges of explosives, particularly the 5 free flowing grades of dynamite of bulk form.

Among the objects of my invention are: To provide a powder loading device having high standards of safety; to provide a means for rapidly fllling a bore hole with bulk explosives; to provide an apparatus for charging a bore hole with pulverous explosives, utilizing air as a conveying medium; to provide an apparatus for charging a bore hole with powder admixed with compressed air; to provide a powder loading device which will clean out all powder grains during use; to provide an apparatus for charging a bore hole with bulk, free flowing powder with the assurance that all the powder will be loaded; to provide such an apparatus wherein all movable parts are guarded against lodgment of powder grains therein; to provide a loading valve for a powder receptacle which is safe in operation; to provide a loading valve for such a receptacle which will withstand air pressure and which is incapable of exerting sufllcient pressure on powder grains to initiate oxidization; and to provide a safe powder loading valve which may also be utilized to grade powder passing through it.

My invention possesses numerous other objects and features of advantage, some of which, together with the foregoing, will be set forth in the following description of specific apparatus embodying and utilizing my novel method. It is therefore to be understood that my method is applicable to other apparatus, and that I do not limit myself, in any way, to the apparatus of the present application, as I may adopt various other apparatus embodiments,- utilizing the method, within the scope of the appended claims.

Other broad objects may be more fully understoodby direct reference to the drawing, wherein:

Figure 1 is a longitudinal sectional view of one embodiment of my invention, taken through the powder loading device.

45 Figure 2 is a longitudinal sectional view of a diflerent loading valve embodiment than is shown in Figure 1.

In my prior patent, No. 1,946,780; issued February 13, 1934, I have described a powder loading device of the same general character as is here presented except for the fact that in the present device I use a different air distribution system and a different loading valve.

I have found that in constant operation of such a device, every possible precaution must be taken in order to prevent stray powder grains from being caught between metallic surfaces where the least pressure applied to them might cause ignition. It is impossible for users of the device to learn by experience in this respect, because an accident almost invariably results in the death of the operator. It is therefore necessary to make such a device absolutely foolproof from the beginning, and the present device has been designed to the end that nowhere is it possible for powder grains to enter any bearing or metal-to-metal contact.

Referring directly to the drawing, a receptacle l is provided at the lower end with a coned outlet end 2, provided with a cleanout plug 3. This cleanout plug must never be opened, of course, in the field. The cone bottom is also provided with a blow pipe connection 4 leading the powder into a blow pipe 5, which is usually flexible in form, and provided with a terminal tube which is inserted into bore holes. Inasmuch as the blow pipe is no part of the instant invention it has not been shown in its entirety. It should also be understood that the blow pipe connection 4 is not to be removed in the field in order that no powder grains may be crushed in the threads.

The conveying power in my loading device is compressed air supplied through a supply pipe 6 and under the control of a valve 1. The outlet of the valve enters a receptacle boss 8 which houses a filter screen 9, in order that no powder grains may be sucked back into the valve in case of pressure reversal.

An air distributing ring I0 is provided, preferably cast integral with and surrounding the side walls of the receptacle and is completely on the outside of the receptacle, so that the inner surface I l is entirely free from projections. This is important, as I have found that if any projection is lefton the inner surface, eddies are formed and small amounts of powder are left in the casing in the eddies, and one of the most important features of my present device is that it will load all the powder and not leave a single grain in the receptacle after the charge has been blown.

The distributing ring it passes air into the interlor of the receptacle through a plurality of apertures, these apertures being so bored as to direct the air to different portions of the interior of the device. For example, immediately adjacent the air connection, and drilled through from the boss 8, is a downwardly directed channel l2 which directs approximately five to ten per cent of the entire air into the outlet opening l3 of the blow pipe. It is the jet of air passing through this hole which moves the main body of the powder into the blow pipe. With many grades of powder, however, the air I Jet thus produced would merely open a hole into the interior of the chamber which are directed variously so that the entire. mass of powthrough the, powder and would not cause evacuation oi the entire chamber. I have therefore provided other. bores from the distributing ring der within the chamber is agitated in such a manner that'no portion of the powder may be evacuated without the rest of the powder, accompanying it'or following it. I Thus, for example,

I'provide certain bores it and I4 directed upwardly. and others I! and i5. bored tangentially not be removed in the field. Thus-by the proper masadirect it toward the outlet, and force it arrangement'of holes from the distributing ring 1 into. the chamber, I agitate, the mass, rotate the through the outlet 11 i such, a manner that no powder remains in the device. I v

Inasmuch as the loading of the-receptacle is. the mostdangerouspart of the entire proceeding, I have'provided my powder receptacle with spe-' Y cial valves which will insure that no powder may ignite. For example, in my former machine I have shown a screw threaded cap. While there havebeen no accidents with this-type of device,

' extreme care hasto be taken that all powder grains. are removed from the threads before replacing the cap. This has two very distinct disadvantages; first, a' large amount of time is con .sumed in sochecking the threads; and secondly.

carelessness is bound to occur eventually. Furthermore, the loading valve must be operated in the field if the machine be operated at all.

I have shown one form of safety loading valve in Figure 1. Here, a valve is made in the form of an inverted cone and supported on a valve stem II. The valve itself is preferably formed entirely of soft rubber, and seats against a soft rubber valve seat 22 in the form of a ring around the upper portion of the receptacle, thus defining a valve opening. A loading funnel 23 is clamped to the upper portion of the receptacle and carries a bearing bracket 24 having an axial bearing 25 through which the valve stem 2i operates. The lower entrance 26'to this bearing is provided with a powder-excluding sleeve 21 clamped at the lower end to a sleeve fitting 20, and at the upper end to a bearing fitting 29. This sleeve is preferably of soft, elastic rubber and acts as a spring to seat the valve. If, however. it is not desirable to use an elastic sleeve in this position, a return spring may be inserted between the bracket 24 and the valve rod in a manner immediately apparent to anyone skilled inthe art, in order to seat the valve. In this case a resilient but non-elastic sleeve may be used, such as leather.

I The upper entrance l0 of'the valvebearing is similarly protected with an upper sleeve 3| closing the bearing entrance in exactly'the same manner, and attached at the upper end to an adjustableclamp 32 which may be positioned on the valve stem at any predetermined position to regulate the length of stroke of the valve 2| so that the distance between the valve 20 and the valve seat 22 may be regulated a predetermined distance. Thus. when powder is poured inthe loading vfunnel 2!, powder grains larger than.

the opening of 'the'valve cannot pass 'there- I through, and the'device acts to prevent such' ceptacle to cause an eddy and a consequent powderdeposit;

The operation of the device is simple. To load.

pressure isplaced upon a terminal operating knob 33 fastenw to the valve stem, and the entire valve assembly is pressed downwardly to form an opening at the lower end of the loading funnel. While this opening is being maintained, powder is poured into the funnel and falls through the opening into the receptacle. After-the: desired amount of powvtier has been loaded, the valve is allowed toreturn to tlre'closed position; the end of blowpip'e' S is positioned in the hole it is deslredto fill; air is admitted to the'receptacle by operating'val've l;

and the powder is blown into the hole. During" the operation of the valve assembly no powder grains can enter the'bearing. and even if powder grains are caught between the valve 20 and the seat 12 they are caught between two surfaces of. a

soft rubber, and irrespective of the pressure ex- 1 '20 is purposely formed of such a shape that air I '7 erated' thereon, will not be ignited. The valve pressure will aid in the seal.

In Figure 21' have shown another form of valve which has been .foundsatisfactory, the valve itself being in the form of a soi'tv rubber plug 1! having an interior chamber 36, the plug at atmospheric pressure being sufficiently small to I enter a substantially spherical valve seat ll formed at the junction of the receptacle andtlre the seal is between metal and soft rubber instead relatively hard.

Both valves as described are incapable of igniting powder grains, and'form an eifective seal against the air pressure within the receptacle.

I claim:

1. A powder loading device, having a cylindrical loading chamber, a blowing chamber disposed thereabout. a plurality of ports between said blowing and loading chambers, an intake valve surmounting said loading chamber, said valve comprising a soft, resilient, member having an inverted conical shape, a loading funnelfixed upon said loading chamber and having a soft, re-

silient, valve seat disposed therein so positioned as to seat said valve, 9. frame supported on said funnel, a sleeve supported thereon, a valve stem slidably positioned therein fixed to said valve, resilient means for positioning said stem vertically, and resilient closure members attached to said stem and said sleeve member.

2. In a powder loading device, a loading valve assembly comprising a valve seat formed of soft, resilient, material positioned upon said device, a. loading funnel fixed thereupon, a supporting framework fixed upon said funnel, a sleeve fixed vertically in said frame, a valve stem slidably positioned in said sleeve, an inverted conical valve of soft resilient material so positioned and arranged upon the bottom of said stem as to engage said seal: tightly under pressure from said loading device, and resilient sleeves forming a seal between said valve stem and said sleeve member.

JOSEPH C. COSTEILO.

Images